Monday, December 3, 2012

Remembering The Dolby Encoded Stereo FM Broadcasts And The Cassette Tape Deck Hi-Fi System


Working musicians back then often cringe at the idea, but do older hi-fi enthusiasts still remember the time when the hi-fi cassette tape deck and the FM tuner worked as a complete “recording system”?

By: Ringo Bones

Working musicians back then whose livelihoods are more or less solely dependent on the revenue of the sales of their copyrighted works often frown upon the prospect of the masses relying as their main recorded music source off-air recording from FM stereo broadcasts. Worse still, near the end of the 1970s, a number of FM stations being run by broadcasters / engineers with “Golden Ears” started to broadcast their music programs in a format called “Dolbyized FM” or “Dolby-Encoded FM broadcasts” where a hi-fi enthusiast with a well-aligned and set-up hi-fi cassette tape deck could “potentially” make off-air recordings whose sound quality that’s as good as or even better – and judging by my first hand experience of finding such cassette tapes in recent garage sales and swap meets often way better – than prerecorded music cassette tapes sold by major labels in licensed music stores. Even though no “integration” yet exists between the i-Pod and the “legal and licensed” online music stores selling downloadable digital music in the form of preemphasis for jitter reduction and what have you – was the “integration” between the hi-fi FM tuner and the hi-fi cassette tape deck via Dolby-encoded FM stereo broadcasts the only time in history where there is system integration between broadcasting and home recording?

Since big-wig engineers running those online “licensed and legal” digital music downloads seems to be sitting on their asses when it comes to pushing for better sound quality, I’ll just reminisce about the good old days of using your hi-fi cassette tape deck to record Dolbyized FM broadcasts. By the late 1970s, “affordable” hi-fi cassette tape decks – if you consider 400 US dollars affordable back in 1979 – started to enter the market that can integrate with FM stations providing Dolby-encoded broadcasting service. Usually in its Dolby noise selector switch - usually with the 19-KHz pilot tone filter for the cassette tape deck's built-in Dolby noise reduction system to work properly with Dolbyized FM stereo broadcasts, there is a position labeled FM which is used to process audio from an FM station that Dolby-encodes its programs. In this mode, recording-level controls are disabled and the input level is controlled usually by two screwdriver controls – on the rear apron – using the test tones that are periodically transmitted (usually in the wee hours of the morning an hour prior to their regularly-scheduled broadcasts) by FM stations that use Dolby processing. The FM mode also converts the 75-microsecond deemphasis of the tuner’s output to the 25-microsecond required by the Dolby noise-reduction system.

Cassette tape decks that are designed to be integrated with Dolby-encoded FM broadcasts are usually equipped with recording heads that are an engineering tour-de-force in comparison to their early 1990s era siblings because cassette tapes recording heads used in such machines back then had to be driven to about +10dB with most tapes before third-harmonic tape distortion reached the reference 3 percent level. While ones made by leading brands – like Sony, Nakamichi and Teac just to name a few -  had to be driven to +13dB before the 3 percent third-harmonic distortion mark is reached. Recording heads used in “affordable” cassette tape decks made around 1994 or later started to reach the 3 percent third-harmonic distortion mark if the signal reaches +4dB – even with metal tapes!

Back in the late 1970s and early 1980s, a good cassette tape deck that is designed to cope with the likely “excesses” of the Dolby-encoded FM broadcasting system usually have a headroom of 7 to 10dB beyond the Dolby level before distortion reaches 3 percent. Therefore, Dolby-encoded FM programs can be recorded with fully effective Dolby operation with no risk of tape saturation and the resulting loss of high frequency signals and increased distortion. And their VU meters are accurate to within 1dB of the correct 200 nW/m flux level for a standard Dolby tape.

On most recorders back then, if the FM Dolby signal levels are adjusted correctly for the Dolby system, with 50 percent modulation corresponding to a Dolby-level meter indication on the recorder, 100 percent modulated peaks will be at +6dB and will almost certainly overload the recorder. The only alternative in most cases is to set the Dolby tone from the FM transmitter (50 percent modulation) several decibels below the meters’ Dolby points, which can degrade frequency response and noise reduction but will not distort. These examples are based on recording the signal without decoding – a theoretically preferable approach. Often, the easiest solution is to decode the Dolby-encoded signal and record it in that form at correct levels.

Thursday, November 29, 2012

Where Does Tape Hiss Come from?


Even though there’s already a number of ways invented to reduce it to near inaudibility, but can you still remember when last time you asked: “Where does tape hiss come from?”

By: Ringo Bones

Believe it or not, all forms of electronic devices generate noise largely because a noise voltage is generated by the random state of movement of free electrons since they tend to dodge to and fro from atom to atom in a random manner. Thus all current-carrying components can contribute to the overall noise signal but those at the front-end of the channel of high amplification devices (like phono head preamplifiers and tape head amplifiers) are the most critical.

The noise produced by the electrons whizzing about within the electronics – including the power-supply hum of a well designed cassette tape deck – however is negligible compared with the noise produced by the tape passing over the replay head. In most situations, the noise level of the main power amplifier electronics is approximately 15dB below that of the combined noise generated by the cassette tape deck’s front-end preamplifier and tape hiss. Thus it is the tape noise which is the most troublesome in audio systems built around hi-fi cassette tape decks.

Tape noise or hiss – whether from analog based tape systems like open-reel tapes, 8-Tracks, cassettes or even Sony’s famed Elcaset – primarily results from the lack of homogeneity of the metal coating or other magnetic medium used. Tape hiss actually has a frequency that starts from 500-Hz, the annoying level, and then extends within 2,000 to 3,000-Hz, the unbearable level. Even though tape noise steadily remains constant with increasing frequency, the hiss that irritates most hi-fi enthusiasts the most mainly lie within the 500-Hz to 3,000-Hz part of the audible spectrum thanks to the Fletcher-Munson Equal Loudness Contour response of the human hearing that makes the 2,000 to 3,000-Hz region the nexus of human hearing audibility.

At present technology, the ferrous particles – or other “advanced” magnetic formulations – can never be distributed absolutely uniformly throughout the coating and the resulting aggregation of the discrete magnetic particles create their own discrete magnetic fields which during replay manifest itself as a noise electromotive force or EMF at the playback head and thus be amplified along with the desired audio signal. And by the way, noise is also produced from the mild irregularities in the traction of the tape towards the record head pole pieces during recording – which explains why during much of the 1980s, the heyday of the cassette tape, manufacturers made increasingly elaborate shell structures and internal mechanisms of their flagship blank cassette tapes as a way to further reduce tape hiss.

Thursday, November 15, 2012

Was Sony’s Elcaset Better Than Philip’s Compact Cassette?


Was this now largely forgotten intended for domestic use audio recording format really much better than Philip’s compact cassette?

By: Ringo Bones

Yep, Sony’s Elcaset is one forgotten sad failure of a domestically intended audio / music recording format supposedly launched as a much better engineered “replacement” for Philip’s compact cassette. Even a Time magazine tribute to former Sony Corp. CEO Akio Morita back in December 7, 1998 never mentioned Elcase while William Lear’s Eight-Track tapes and Peter Carl Goldmark’s 33 1/3 RPM vinyl LPs were mentioned. But is or was the Elcaset truly better than the compact cassette as an audio and music recording medium?

At the time – during the early 1970s - when Sony intended to launch a more user-friendly domestic audio recording format that is of higher fidelity than Philip’s compact cassette, cassette tape formulation technology, as we know it by the 1980s, was still in its infancy. Metal / Type IV position cassettes were yet to be invented – and even TDK’s famed cobalt-doped Super Avilyn Type II high-bias position tapes were still years away from being invented and marketed. Even Sony’s own top-of-the-line hi-fi cassette tape decks manufactured under license from Philips has a high-frequency bandwidth that barely crawls above 16,000 Hz. And don’t forget Sony’s “jealousy” with the runaway success of the compact cassette by the start of the 1970s finally made their engineers hatch a plan to launch a “better-sounding” replacement.

Maybe as it was the only format launched by Sony that was bigger than its intended competitor that might have contributed to its failure, the Elcasete – due to its higher tape speed – at 3 ¾ inches per second twice that of the compact cassette’s 1 7/8 inches per second – easily exhibited better wow and flutter characteristic than its smaller competition. And using tape that’s the same thickness, 6.3 mm as standard quarter-track open reel tapes (like those Barclay-Crocker open-reel tapes) – compared to the compact cassette’s 3.8 mm thickness – Sony’s Elcaset easily exhibited better signal-to-noise ratio, higher recording levels – which amounted to way better sound quality than the Philip’s compact cassette. Elcaset decks easily reached 25,000 HZ during tests at the time – in 1976 – where most top-of-the-line 1,000 US dollar compact cassette decks can barely crawl past the 16,000 Hz mark. Running more tape at higher speed past the head easily gave Elcaset a greater potential performance advantage over the compact cassette, even if bulk and cost were the price to pay. But why did Elcaset fail?

According to hi-fi enthusiasts old enough to experience the format launch first hand – back in 1976, Sony never made and marketed prerecorded music Elcasets for them to compare wit their do-it-yourself audio and music recordings. Not to mention audio enthusiasts at the time never “wanted” anything better than their quarter-track open-reel tapes, which was the “ultimate” in domestic audio recording and music playback at the time. Sony’s Elcaset uncomfortably fell somewhere in between – hardcore hi-fi enthusiasts consider “closed cassettes” with lower-fidelity convenience. And even while running at 3 ¾ inches per second, audiophile quality open-reel prerecorded tapes – like those from Barclay-Crocker – ran at 7 ½ inches per second, easily providing better sound than Sony’s Elcaset. At around 18 or so months after its release, Sony Elcaset tape decks – like the EL5 and EL7 recording decks and even their ELD8 “walkman-type” portable Elcaset player were soon heavily discounted, and by 1979, Sony’s Elcaset dies with barely a whimper.

These days, one can sometimes find old but still in perfect working condition Elcaset decks being sold in weekend hi-fi swap-meets  at around 10 to 12 US dollars or so – even with a complementary set of 10 or more unused blank Elcaset tapes still enclosed in their original shrink-wrap unopened probably since 1976. Surprisingly, the Elcaset blank tapes often given away as freebies on second-hand Elcaset decks are, more often than not, the premium Ferrichrome type. I managed to buy use one myself back in the mid 1990s and all I can say is that Elcasets are way better – sound quality wise than Philip’s compact cassette. Modified cassette tape systems that ran at 3 ¾ inches per second – twice that of the standard cassette tape speed of 1 7/8 inches per second – still can’t compete with Elcaset especially in the critical mid-band region, which the soul of music resides.

 Even when recording from a CD Redbook standard 16-bit 44.1 KHz sampled Sony Super-Bit-Mapped release of Miles Davis’ Kind of Blue album, Sony’s Elcaset obliged me and most users I assume, with that hard-to-define “out-of-speakers” quality that was so appealing about open-reel tapes – or high-end vinyl LP replay and 1990s era CD set-ups that cost over 5,000 US dollars. If you are lucky enough to find a still pristine 2-channel open-reel first generation master tape to dub from, Sony’s Elcaset could probably provide better sound quality than Super Audio CDs!

Thursday, October 25, 2012

A Higher Reference Frequency For Selecting Cassette Tape Bias Level


A difference of 2 to 3 dB in MOL is already a big deal in the cassette tape recording world but are there any benefits of using a higher reference / test frequency in selecting the right recording bias level?

By: Ringo Bones

Even until well into the 21st Century, the reference frequency that is used by leading cassette tape and cassette deck manufacturers are either still 315 Hz or 1,000 Hz in order to set the MOL or maximum output level in choosing the proper bias current level when recording. But are there any benefits in choosing a much higher reference frequency when selecting the “optimum” recording bias level to obtain the chosen cassette tape’s MOL?

During a study conducted by their R n’ D engineers during the latter half of the 1970s, Hitachi – one of the leading Japanese cassette tape deck manufacturers of the time - determined that the bias level giving a peak output at 1,000 Hz is roughly 33 percent higher than that which gives a 5,000 Hz MOL for “Normal” ferric-oxide tapes, roughly 25 percent higher for chromium-dioxide tapes and 11 percent higher for ferrichrome tapes. Armed with such statistical information, Hitachi was able to create a system that was later used in their self-adjusting cassette tape decks that adjusted for MOL at 1,000 Hz while actually testing a tape at 5,000 Hz. Although a tape-type switch – i.e. Normal/Type-I, Chrome/Type-II, Ferrichrome and Metal/Type-IV – must still be used to make sure that the right correction factors are introduced.

This cassette tape recording “phenomena” discovered by Hitachi’s R n’ D engineers at the time became the “brilliant engineering solution” of its day when it comes to designing self-adjusting cassette tape decks that most enthusiasts can still afford because competing designers of self-adjusting cassette tape decks near the end of the 1970s have decided against incorporating distortion analyzers in their cassette tape deck designs – even their premium models – because the complexity and expense is deemed a bit too much for the market at that time. Instead they all aim to use various schemes to aim for maximum output level (MOL) at some specific frequency – usually around 1,000 Hz. But it looks like Hitachi’s method of using a higher frequency was deemed as a brilliant cost-effective engineering solution back then.    

Wednesday, September 5, 2012

Record Bias Self-Adjusting Cassette Tape Decks: Technological Tour De Force?


Given that this late 1970s ingenious innovation to further optimize the recording performance of the “lowly” compact cassette, did record bias self-adjusting cassette tape decks truly qualify as a technological tour de force? 

By: Ringo Bones 

Every serious cassette tape recordists during the late 1970s may don’t have yet the “technical vocabulary” to the problems besetting them arising from the Philips compact cassette performance and manufacturing limitations, it seems that every advances in technology aimed at extracting every bit of performance of the lowly compact cassette seems to be a fast track to nowhere. Even with the 4 types of broadly standardized cassette tape types, namely the: Type-I or Normal Bias 120 microsecond entry-level tape, Type-II or High-Bias 70-microsecond Chrome Position cassette tape, Type-III or Ferrichrome cassette tape purposely built for the “acoustically noisy” car environment and the Type-IV or Metal Position 70-microsecond metal particle cassette tape, which at the time, represented the pinnacle of cassette tape technology for those wanting open-reel tape performance in a compact cassette tape package. So “technological utopia” for the lowly cassette tape has finally been reached, right? 

When recording tape – whether open-reel or compact cassette types – is improved in any significant way – even if the change is something as ostensibly physical as a smoother coating surface, with the magnetic particles themselves left unchanged – the tape now behaves differently with real-world tape decks as an electromagnetic entity. Generally, the tape now requires – or at least would benefit from – a different level of recording-bias current, followed by the obligatory touch-up of the tape deck’s default record equalization curve. Unfortunately for the typical everyday cassette tape recording enthusiasts, these are adjustments that require good – and usually expensive – instruments and a certain amount of technical expertise to accomplish; Not to mention that these adjustments are also very time consuming to perform. 

Cassette tape recording enthusiasts back in the late 1970s more often than not experienced first hand the “rude awakening” of buying a handful of cassette tapes from their local retailer for the sole purpose of finding out which brand suit them best only to find out later that all of them require somewhat different levels of fine tuning of the recording bias and equalization of the cassette tape deck they currently own. Optimizing your cassette tape deck for each one so that you can evaluate noise levels and other important performance criteria for cassette tape recording will more often than not prove to be a project of Herculean proportions. Then there’s also the problem of cassette tape manufacturers’ batch variations. For the sake of example, TDK’s cassette tape production for June is not likely to be identical to the production batch made previously in March. Very serious cassette tape recordists at the time often buy in quantity from a single batch and resign themselves to readjusting their cassette tape decks when their supply stash of cassette tapes ran out and a new batch must be investigated. This is hardly a formula for progress thus the raison d’être for the self-adjusting record-bias cassette tape deck was born. 

The user-selectable tape type accommodation abilities of record bias self-adjusting cassette tape decks and the ease it can perform these “arduous” tasks has been widely hailed at the time as the solution for this very dilemma. Back then, they look as if they are the next step forward in the technological evolution of the few innovative cassette tape decks already incorporating two-tone oscillators that enables the user to achieve a reasonably flat frequency response with virtually any cassette tape out on the market when it comes to do-it-yourself field recording of music and other “real” acoustic events or just simply dubbing the recorded contents of other prerecorded cassette tapes being played from a separate dedicated deck. 

The most advanced of the first generation of these record bias self-adjusting cassette tape decks were equipped with 4-bit analog to digital converters to accurately sample the MOL of the test-tones being recorded on the cassette tape under evaluation and a 3-bit floating point microprocessor system to process the data in order to perform the necessary adjustments to dial in just the right amount of record bias to enable the tape deck to automatically “fine tune” the maximum MOL while minimizing total harmonic distortion and flat frequency response that the cassette tape under evaluation is truly capable of. 

Even though such analog-to-digital conversion and processing power seems lowly by today’s standards, it enabled those early generations of self-adjusting cassette tape decks to perform 96 steps of bias level adjustments and 16 steps of EQ and sensitivity adjustments – with 0.5 dB of resolution. With a good tape, these early decks were said to be able to maintain a recording frequency response tolerance – or flatness – of plus and minus 0.5 dB over much of the audio frequency range. This sort of performance will only do wonders to these tape decks’ ability to portray a fairly accurate imaging and sound-staging of the acoustic event in the space it is trying to record. 

Thanks to this record bias self-adjusting cassette tape decks, there will be no more tape jungle to flounder through for the serious cassette tape recordist. He or she will be able to buy an armload of different manufacturers’ cassette tapes, take them home, and in the course of a civilized, low-pressure evening decide for himself or herself what his or her brand is going to be, without the worry that a non-compatible cassette tape deck is making a good tape look (or sound) bad. By the same token, cassette tape manufacturers will finally be able to concentrate their full efforts on making a genuinely better cassette tape. It will not be just a somewhat better tape that has been compromised a little because it must match the factory-set performance and adjustment profile of earlier generations of cassette tape decks already in the hands of potential customers. 
     

Monday, August 27, 2012

Bias Level: The Be-All-End-All of Cassette Tape Recording?

Even though the standards of the high-frequency pre-magnetization or a.c. bias became more or less sacrosanct around World War II, does it truly represent the most important factor in the serious cassette tape recordists’ life? 

By: Ringo Bones 

The newer hi-fi generation weaned on better CD players and the recent vinyl LP revival may be too young to remember, but there was a time when recording bias level – i.e. the alternating current used in electromagnetic preconditioning of tape-based analog audio tape recording was the be-all-end-all of the serious cassette tape recordists’ life. Around the time when B-List actor Ronald Reagan just got nominated by the US Republican Party to run as the next president of the United States and the Ayatollah Khomeini was too busy enjoying the spoils of his “Islamic Revolution”, some upmarket cassette tape decks started sporting 4-bit microprocessors that automatically optimize blank cassette tape and cassette tape deck co-performance beyond the Normal Bias / Type-I, High Bias / Type-II, Ferrichrome / Type-III, Metal/Type-IV selector switch of the typical cassette tape deck at the time. And many enthusiasts at the time who press cassette tape for high fidelity music recording use eventually found out that even a little too much applied recording bias level can cause erasure of high frequencies – the very spectrum that tends to give life to recorded music. Given that tape recording bias level for all intents and purposes could be considered at the time as the most important factor in the serious cassette tape audio recording, what is it and what makes it so special? 

Around World War II, the manufacturer of the AEG/Magnetophon R22 magnetic tape recorder for recording and broadcasting more or less made the standard for setting bias levels for all tape-based analog audio recording. Tape bias alternating current frequency is usually set at least five times the highest audio frequency to be reproduced in order to minimize the audible interaction between the pre-magnetization a.c. bias and the harmonics of the highest audio frequencies – a sort of “Nyquist Criterion” for analog audio tape-based recording. Thus if you seek a tape recording frequency response that goes up to 20,000 Hz, the bias should be at least 100,000 Hz. And some upmarket tape decks manufactured between the late 1980s and mid 1990s have their record bias frequency set as high as 125,000 Hz!  

During the cassette tape’s heyday, bias level has been the tricky consideration in the whole high fidelity music recording process, in large part because the optimum record bias level for a tape is largely a controversial issue. Depending on your criteria, you could choose a bias level – either manually or via your newfangled self-adjusting cassette tape deck’s built in 4-bit microprocessor – that: (1) maximizes the output MOL of the cassette tape at some reference frequency – usually 1,000 Hz; (2) minimizes third-harmonic distortion from your tape – for a test frequency of your choice, but often one in the vicinity of 1,000 Hz; (3) minimizes modulation noise; (4) minimizes intermodulation distortion in any of a number of two-tone tests; or (5) satisfies any of a number of “ideal” criteria for the relative useable output levels from the cassette tape at low and high frequencies. 

Wednesday, August 22, 2012

Play Trim: A High-End Cassette Tape Deck Necessity?


Introduced around the mid 1990s in upmarket high-end cassette tape decks, does the Play Trim facility qualifies as a high-end cassette deck necessity? 

By: Ringo Bones 

High-end cassette decks circa 1995 might see like an oxymoron to us audiophiles but it became a buzzword to audio product retailers and tenured hi-fi reviewers during the period. But does the 1990s era compact cassette innovations during the time managed to give the humble Philips compact cassette a few more years worth of reprieve from being phased out? 

In practice, the Play Trim facility in upmarket cassette tape decks was hailed by those who still use the compact cassette as their primary music recording and listening medium during the 1990s as a very useful facility to get the best – or was in most – from prerecorded music cassette tapes. Play Trim eliminated the associated dullness of record store bought prerecorded music cassette tapes by acting as a specialized treble control placed in front of the cassette deck’s built-in Dolby noise reduction system. 

To casual listeners, most Play Trim equipped cassette decks introduced in the 1990s allowed prerecorded music cassette tapes to sound well enough – in comparison to the compact disc during that period. And also, most Play Trim facilities offered plenty of adjustment to counter the inherent dullness – i.e. rolled off high frequencies – that afflicts many prerecorded music cassette tapes released by major music labels at the time, especially if the listener opts to switch the Dolby noise reduction on to reduce tape hiss. 

The Humble Philips Compact Cassette Tape: Past Prologue?


This “reluctant” music recording medium’s demise might have been a tad exaggerated, is the humble Philips’ compact cassette still alive and kicking? 

By: Ringo Bones 

Even though it seems to have vanished overnight in some parts of the world back in 2009, the internet is still abuzz with testimonials that the humble compact cassette is still used by revolutionary firebrands to spread their radial political messages in parts of the world yet to enjoy the benefits of Web 2.0. Not to mention independent record labels of the punk rock, death metal, black metal  genre who don't have their own vinyl pressing plants for making 7-inch 45-rpm singles. Given the reluctant music medium’s illustrious 50-year history, will Philips’ compact cassette ever “retire in dignity”? But first, an illustrious look back to the reluctant music recording medium that could. 

Back in 1963, the European arm of Philips launched the compact cassette. It was primarily introduced as a dictation medium for use in Philips office voice / dictation recording machines that were then licensed to be manufactured by Norelco. And there were very blatant signs that Philips never engineered the compact cassette to be a high fidelity music recording medium because of the inherent narrow track width and the slow tape speed of 1 and 7/8 inch per second (4.76 centimeters per second) making it prone to tape saturation. William Lear’s 8-Track tapes that runs twice as fast and has twice the track width easily bettered the cassette as a convenient consumer-based music recording medium and quarter-track open-reel tapes at the time offered even higher performance when run at seven and a half inches per second. 

But around 1967, there were some visionary high fidelity enthusiasts who placed it among themselves to make Philips’ humble compact cassette into a viable true high fidelity music recording medium. During that year, hi-fi manufacturing visionary Henry Kloss heard about Ray Dolby’s noise reduction system initially intended for professional – as in recording studio – applications. It was Kloss who pushed for a consumer version of the Dolby noise reduction system, which Kloss originally saw as a boon to open-reel tape users. Some months later, Henry Kloss linked the Philips compact cassette system with a previously unsuccessful DuPont product – chromium dioxide tape. Thanks to the magical midwifery at which Henry Kloss excels, these seemingly disparate inventions helped make the Philips compact cassette – originally introduced for office dictation recording purposes – into a high fidelity music storage medium that eventually went on to surpass the vinyl LP and even CD sales in 1989. 

Famous and established musicians from the 1960s also did their part in pushing the Philips compact cassette into a high fidelity music playback and storage medium. Near the end of 1967, The Rolling Stones’ guitarist Keith Richards used an early Philips Norelco cassette recorder originally marketed as an office dictation recording machine to record the now distinctive guitar parts of their iconic song Street Fighting Man. Thirty years later, the late Ted Hawkins’ 16 tracks from the McCabe’s show were originally recorded on standard cassette – and while they’ve been improved on the 1997 The Final Tour album via 1990s era HDCD processing, these tracks still exhibit limited dynamic range. 

And before us mere civilians were taught by Tim Berners-Lee on how to master the then US DoD’s DARPANET – now known as the internet – if a revolutionary firebrand wants his or her messages to go “viral”, recording your speeches on scores on cassette tapes was the only way to go. That is if the despotic government you intend to overthrow keep jamming your CB radio transmissions. The Iranian religious leader Ayatollah Khomeini used the cassette tape route to make his Islamic Revolution a runaway success while toppling the Shah of Iran back in 1980. And did you know 50 years before thumb drives / USB drives became de rigueur mass data storage devices, the lowly Philips compact cassette was once used to store chunks of computer data – even its operating system as was once shown in that James Bond movie called Diamonds Are Forever?